Short versions of the telephone motor functional independence measure for use with persons with spinal cord injury

Objective: To determine if the motor ability of persons with spinal cord injury (SCI) can be reliably estimated using a subset of the 13 Functional Independence Measure (FIM) items. Study Design: FIM item subsets of 5, 6, or 7 items were selected using one of five strategies: random, coefficient alpha maximization, spread across the range of item difficulties, optimization by neurologic category, and individual optimization. Motor ability estimated by these 15 subsets was compared to the 13-item estimate, using intraclass correlation coefficient (ICC), Rasch calibration person reliability estimate, and other indices of reliability. Subjects: Subjects were 4,128 persons with SCI, 1 to 25 years postinjury, interviewed for annual research follow-up using the FIM. Results: All subsets had high ICC reliability (>.90). Subsets of 7 items performed generally better than those of 6 or 5 items. The best performance was provided by individual optimization subsets. The ICC for the 7-item set thus selected was .99. Conclusion: In annual follow-up, the number of FIM motor items can be reduced almost 50% while maintaining reliable estimates of subjects' motor ability. This approach may also be useful for other applications of interviewing to obtain FIM data, eg, for program evaluation. (C) 1999 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.